Imidazo-s-triazinediones and byrimido-s-triazinediones

ABSTRACT

Herbicidal triazenediones of the formula   WHEREIN R1 is certain organic radicals and R2 is hydrogen or methyl. Exemplary of such compounds is: 3-cyclohexyl-6,7-dihydro-8methylimidazo-(1,2-a)-s-triazine-2,4-(3H,8H) -dione.

United States Patent [1 1 Jewell et al.

[ 3,907,796 Sept. 23, 1 975 lMlDAZO-S-TRIAZINEDIONES AND PYRIMIDO-S-TRIAZINEDIONES [75] Inventors: Richard A. Jewell, Landenberg, Pa.;

Kang Lin, Newark, Del.

[73] Assignee: E. l. Du Pont de Nemours and Company, Wilmington, Del.

[22] Filed: May 24, 1974 [2|] Appl, No.: 473,225

[52] US. Cl...,...., 260/249.5; 71/93; 260/482 C;

260/468 E; 260/553 R; 260/347.3 [51} Int. Cl. C07D 251/08 [58] Field of Search 260/249.5

{56] References Cited UNITED STATES PATENTS 3,637,684 l/l972 Goldman 260/249.5

FOREIGN PATENTS OR APPLlCATlONS 2,254,200 5/1974 Germany Primary Examiner-John M. Ford 57 ABSTRACT Herbicidal triazenediones of the formula R is certain organic radicals and R is hydrogen or methyl. Exemplary of such compounds is: 3-cyclohexyl-6,7- dihydro-8-methylimidazo-l l ,2-a]-s-triazine-2,4- (3l-l,8l-l)-dione.

3 Claims, No Drawings IMIDAZO-S-TRIAZINEDIONES AND BYRIMIDO-S-TRIAZINEDIONES BACKGROUND OF THE INVENTION Johnson Pesticides 72, Chemical Week, June 21 and July 26, I972, lists several commercial and experimental s-triazine herbicides, Among these are atrazine, simazine, prometone, and prometryne:

prometonc promctrync Copending US. Patent Application Ser. No. 348,321, filed Apr. 5, 1973 now abandoned, by Kang Lin (which is a continuationin-part of US. Patent Application Ser. No. 256,249, filed May 24, 1972, now abandoned) discloses a class of s-triazines of the general formula:

where X is oxygen or sulfur;

R is certain organic radicals including certain openchain and cyclic radicals;

R is hydrogen. lower alkyl, or certain cations;

R is hydrogen or certain lower alkyls; and

R is certain organic radicalsv These compounds are disclosed as being useful as herbicides.

The compounds of the present invention result from efforts to develop new herbicidal compounds SUMMARY OF THE INVENTION This invention relates to novel compounds of the following formula and their use as herbicides:

wherein R is alkyl of 2 through 8 carbon atoms, alkenyl of 3 through 6 carbon atoms, alkynyl of 3 through 6 carbon atoms, cycloalkyl of 4 through 8 carbon atoms, cycloalkenyl of 5 through 8 carbon atoms, cycloalkylmethyl of 4 through 9 carbon atoms, cycloalkenylmethyl of 6 through 9 carbon atoms, bicycloalkyl or hicycloalkenyl of 7 through 10 carbon atoms, bicycloalkylmethyl or bicycloalkenylmethyl of 8 through 1 1 carbon atoms, trimethylcyclohexyl, tetramethylcyclohexyl, or tetrahydro-2- pyranyl; or

, III

This invention also includes herbicidal compositions methyl group; containing the above compounds as active ingredients R is methyl; and and methods of controlling undesirable vegetation by n is 2. applying the compounds and/or compositions The most preferred compound from within this group 5 is 3-cyclohexyl-6,7-dihydro-8-methylimidazo[ l,2-a]-s- DESCRIPTION OF THE INVENTION triazine-2,4-(3H,8H)dione.

Preferred Cmnpounds Synthesis of the Compounds Certain of the compounds of formula I are preferred The compounds of formula I can be made by the probecause of their higher herbicidal activity and ease of IO cess described and exemplified below: synthesis. These include those compounds of formula A method for preparing the compounds of this invenl where tion starts with a Z-methyl-2-thiopseudourea salt such R is alkyl of 3 through 6 carbon atoms, cycloalkyl of as the sulfate or hydrochloride. A schematic represen- 5 through 8 carbon atoms, or cycloalkyl of 5 tation of this method is shown by equations 1 through through 8 carbon atoms substituted with one 15 5 below:

SCH

R; /L RI 5 wherein:

R,. R and n are as previously defined;

M is an alkali metal; and l X and X are leaving groups such as p-toluenesulfon ate. methanesulfonate. chlorine. bromine. or io dine.

A suspension or solution of compound 1 is made in the selected solvent and treated with methylchloro formate (Equation 1 or an isocyanate of the formula R NCO (Equation la) until the reaction is complete. The product. a l-carbomethoxy-2-methyl-2- thiopseudourea (compound 3) or a l-substituted-4- methyl-4-thiopsuedobiuret (compound 3a) is treated with an isocyanate of formula R NCO (Equation 2) or methyl chloroformate (Equation 2a) to give compound 5. A solution of compound 5 in a suitable solvent is treated with an alkali metal alkoxide to give the salt 7 (Equation 3 A solution or slurry of compound 7 in a selected solvent'is reacted with a 1.2-disubstituted ethane or l.3.-disubstituted propane (compound 8) in which the substituents X and X are leaving groups such as those listed abovesto give compound 9 (Equation' 4). A suspension or solution of compound 9 is then reacted with methylamine or ammonia'(compound in a suitable solvent to give compound I 1 (Equation The product, an imidazo [-l .2-a]-s-triazine- 2,4(3H.8H)-dione or a pyrimidol l,2-a]-s-tria7.ine- 2.4(3H)-dione. can be isolated by conventional techniques which in some cases include the use of chromatography for purification.

The solvents which can be used in these reactions are water. methanol. toluene. benzene. xylene. monochlorobcnzene. nitrobenzene. methylene chloride. dimethylformamide. trichloroethylene. and tetrachloroethylene. The preferred solvent for the conversion in Equation 1 is water although mixtures of water and the organic solvent listed above can be used. A mixture of water and organic solvents is preferred for the reaction in equation la since the isocyanate reacts with water to form undesired by-products. The yield ofcompound 3a could be seriously effected by these side reactions.

The reactions 1 and la can be carried out from l0C. to 50C. but preferably from 0 to C.. and most preferably from 0 to 25C.

The pH in reactions 1. la. and 2a can be varied preferably from 6.5 to 11 and most preferably from 7 to The order of addition of the reagents methyl chloroformate and isocyanate (R,NCO) versus addition of aqueous base can be varied. The methyl chloroformate or isocyanate can be added first followed by the aque ous base. but preferred is the simultaneous addition of methyl chloroformate or isocyanate and the aqueous base. The base can be selected from lithium. sodium. and potassium hydroxide. The strength of the base to be added can be varied from H) to 50')? but the higher concentration of base is most preferred because of the lower reaction volume for a given amount of product.

This simultaneous addition of methyl chloroformate or isocyanate and 50% aqueous base gives a higher yield of product 3 or 3a because of the controlled pH conditions and shorter contact time with water required for completion of the reaction.

The reactions 2 and 2a are preferably carried out between 0 and 50C and most preferably between l5 and C.

The compound 5 is preferably treated with 0.6 to 1.3 equivalents of alkali metal alkoxide and most preferably with 0.9 to 1.1 equivalents. The alkoxide can be used as the pure base or preferably as a solution in a suitable solvent and most preferably as a l5 to 3571 solution in the corresponding alcohol.

The solution ofcompound 5 can be cyclized to compound 7 by use of an alkali metal hydroxide. but an alcoholic solventmust be added to dissolve the hydroxide before cyclixation occurs. The cyclization of compound 5 to compound 7 (Equation 3) takes plaee.preferably at 25 to C. but most preferably at 45 to 70C.

The removal of solvent to give a slurry of compound 7 can be carried out under reduced pressure or at atmospheric pressure at a temperature of 20C. to 135C. but most preferably from 25 to 50C. under reduced pressure and from 65 to C. at atmospheric pressure.

The 1.2-disubstituted ethane or l.3-disubstituted propane used in the alkalation of compound 7 is preferably a halosulfonate such as 2-chloroethyl methanesulfonate, 2 chloroethyl p-toluenesulfonate. 3- chloropropyl methanesulfonate. or 3-chloropropyl p-toluenesulfonate. The alkylation reaction is preferably carried out in a polar anhydrous solvent such as dimethylformamide or acetonitrile at 50 to C. When the reaction is complete. the solvent is evaporated under reduced pressure. The residue is treated with a mixture of dilute aqueous base and methylene chloride. The methylene chloride layer is separated. dried. and evaporated to give compound 9. The product can be purified by recrystallization or chromatography or may be used directly in the next reaction.

The conversion of compound 9 to compound ll is carried out preferably in a water-miscible solvent such as methanol. An excess ofaqueous methylamine or ammonia is added to a solution or suspension of compound and the mixture is heated at 30 to 65C. until the reaction is completed. The solvent is evaporated and the crude imidazo [l.2-a]-s-triazine-2.4(3H.8H)- dione or pyrimidol l .2-a]-s-triazine-2.4(3H)-dione is purified by recrystallization or chromotography.

The following Examples and Tables further illustrate this method of synthesis for the compounds of the present invention. Allparts are by weight and all temperatures are in degrees Centigrade unless otherwise indicated.

Example 1 To a solution of 69.5 parts of 2-methyl-2- thiopseudourea sulfate and 47 parts of methyl chloroformate in [.000 parts of water at 0 is added dropwise 56.9 parts of potassium hydroxide in 200 parts of water. The reaction mixture is stirred at room temperature for three hours and then extracted with methylene chloride. The methylene chloride extract is dried and the solvent evaporated on a rotary evaporator to give 45 parts of methyl N-(l-amino-l-methylthiomethylene)carbamate. m.p. 72-77C.

Example 2 74 Parts of the compound produced by Example l, above, and 63 parts of cyclohexyl isocyanate in 300 parts of methylene chloride are stirred overnight. The solvent is evaporated on a rotaryevaporator to give 128 parts of methyl 4-cyclohexyl-N-methoxycarbonyll-thioallophanimidate. m.p. 8586C.

The following compounds in Table 1 can be prepared similarly. I Y

TABLEl m.p. l73-l74.5

m.p. l32-l34 Example 3 100 Parts of the compound of Example 2 is refluxed for one hour with 20 parts of sodium methoxide in 200 parts of methanol. The methanol is evaporated on a rotary evaporator and the triazinedione sodium salt is dissolved in 200 parts of water. The aqueous solution is neutralized with hydrochloric aciddThe solid is filtered off and dried to yield parts of 3-cyclohexyl-6- methylthio-s-triazine-Z,4(1H ,3H )-dione,

The triazines following in Table ll can be cyclized from the appropriate thioallophanimidate in a similar nt.pv 192- I955 mipt I45 I48 Example 4 s N f 100 Parts ol the compound of Example 3 is added to a solution of 23 parts of sodium methoxide in 300 parts of methanol. The mixture is evaporated on a rotary evaporator and the resulting triazinedione sodium salt is dried The sodium salt is placed in 200 parts ol dimeth 'll1ii'ttia|nitle and )7 parts of I-ehloroethyl-p-toluenesulfonate are added The mixture is heated on a steam hath for 1.5 hours and then evaporated under vacuum. lo the residue is added 5H0 parts of meth lene chloride and 500 parts of 2) aqueous sodium eurhonate solution. The mixture is shaken and then the metlnlene chloride layer is dried over anh \'drous sodium sulfate. filtered. and evaporated on a rotary evaporator to afford 7-1 parts of l-(I-ehloroetlrvll-3- cyclohexyl-( -meth 'lthio-s-trialine-l-H l H.3H )dione as a oil. 1.5596.

The following compounds in 'l'ahles Ill and l\' can he prepared similarly h using the appropriate triazinediones and Z-ch|oroeth p-toluenesull'onate or 3- chloroprop \'l p-toluenesullonate:

(all

TABLE "I ('H (H. ,('l

T a ('m'ir; (2Q

lt n n -(I'CH:.

TABLE 1v Example 100 Parts of the compound of Example 4 is mixed with 800 parts of methanol and 7() parts of 4071 aqueous methylamine. The solution is stirred for two hours at C. and then refluxed for one hour. The solvent is evaporated and the residue is chromotographed using SilicAR (C-7 (Mallinckrodt Chemical Works, St. Louis. Missouri) with chloroform eluent. Several byproducts are eluted first; followed slowly by the desired product. At this point the eluting solvent is changed to methanol in order to more rapidly elute the productv The fractions containing the product are combined and evaporated on a rotary evaporator. The residue is triturated in cold carbon tetrachloride and then dissolved in benzene and filtered to remove a small amount'of insoluble material. The benzene filtrate is then evaporated on a rotary evaporator affording parts of 3- eyelohexyl-(w.7dihydro-8-methylimidazol LZ-a ]-s.- triazine-2.4(3H.8H)-dione. m.p. l72l76(.

In a similar fashion the imidazotriazinediones and pyrimidotriazinediones listed in Table below can be prepared by using the appropriate l-(Z-chloroethyhtriazinedione or l-(Lehloropropyl)-triazinedione and methylamine or ammonia.

TABLE V TABLE \'-("ontinued.

TABLE V-Continued TABLE V-Contin ued ((CH- H l,,)

RI R: n RI R: n

('H CH SCH- ,(H CH.-i 2

(H; 2 l' 2 X 0 CH 2 c C)- OQN (l H 2 20 Q 2 F,-,C CH;, 2 (l-Q CH 1 E (l-@- H 1 CH., C CH;, 2

F CH1! 3O Br Formulations of the Compounds CH;, 2 The formulations of the compounds of Formula 1 for use in this invention can be prepared in conventional Cl ways. They include wettable powders, suspensions, and E CH 1 solutions in solvents and oils. aqueous dispersions, granules, pellets, and high-strength compositions.

- Man of these can be a lied directl S ra able for- H 3 PP y P y mulations can be extended in suitable media and used CH 2 40 at spray volumes of froma few prints to several hundred gallons per acre. High-strength compositions are primarily used as intermediates for further formulation. CH 1 Broadly speaking, these formulations consist essentially of about i to 99% by weight of herbicidally active material (including at least one compound of formula I in a herbicidally effective amount.) and at least one of (a) t 2 about 0.1 to 2071 by weight of surface active agents and (b) about 5 to 99% by weight of solid or liquid diluents. -1 More specifically. the various types of formulations will L generally contain these ingredients In the following approximate proportions: 's :i 2 2 2 Q -CH;, 2

i Percent by Weight CH 5 Herbicide Diluent Surfactant l F CH 2 wclllihlc Powders 25-90 044 1-10 I Suspensions or 5-50 40-95 0-10 CH" Solutions Aqueous Dispersions ]()5() 40-89 1-10 M (H;, Granules and Pellets 1-35 65-99 045 High-Strength 90-99 0-10 0-2 Composition t u u G (H;; 2

- The actual percentages that will be desirable for a CHISO CH given composition will depend upon its intended use 1| and the physical and chemical properties of the active ingredients. CH.-,CH2- 3 The compounds of formula 1 can be combined with other herbicides and are particularly useful in combina- I 3-1sec-butyl l-5-bromo-6- methyluracill. diuron |3-(3.4-dichlorophenyl)-I.1- dimethylurea paraquat 1.1'-dimethyl--l.4'- bipyridinium ion). m-t3.3-dimethylureido)phenyl-tertbutylearlmmate. 4-aminoJs-tert-bUtyI-B-methylthioustriazine-5(4HJ-one. and the s-triazines such as 2- chloro-J-ethylamino-fi-isopropylamino-s-triazine. for controlling a broad spectrum of weeds.

'l'ypical solid diluents are descrihedin Watkins et al. Handbook of Insecticide Dust Diluents and Carriers. Sccond Edition. Dorland Books. Caldwell. NJ. The more absorptive diluents are preferred for ettable powders. 'lypical liquid diluents and solvents are described in Marsden. --Solvents Guide. Second Edition. lnterscience, N.Y., 1950. Solubility under 0.1% is preferred for suspension concentrates; solution concentrates are preferably stable" against phase separation at C. McCutcheons Detergents and Emulsifiers Annual, Allured Publ. Corp., Ridgewood, N.J., as well as Sisely and Wood, Encyclopedia of'Surface Active Agents, Chemical Publ."Co.,'Inc., N.Y., 1964. lists surfactants andTrec ommended uses. All formations can contain minor amounts of additives to reduce foam, caking,corrosion,microbiological growth, etc. Preferably, ingredients shouldbe approved by the U.S. Environmental Agency for the use intended. f i

The manner of making and using sucli'herbicidal formulations is described in numerous patents. see. for example. Luckenbaugh. US. Pat. No. 3.309.192: Lous. US. Pat. No. 3.235.357: Todd. US. Pat. No. 2.655.445; Hamm et al.. L.'.S. Pat. No. 2.863.752: Sherer et al.. U.S. Pat. No. 3.079.244: Gysin et al.. US. Pat. No. 2.891.855. and Barrous. US. Pat. No.

Typical formulations are shown in the following examples.

tion with bromacil ethylene ethers The ingredients are combined and stirred to produce a SQlUflOILM'hlClt can be emulsified into water for spraying.

Wetlahle Powder Percent J-cyeIohesyIh.7 dihydroH-methylimidaro-| 1.- La l-s-trinzineJA-t 3H.NH t-dione 1 diatomaceous earth 71.5" dioctylsoditnn sulfosuccinate l low viscosity methyl cellulose The ingredients are thoroughly blended and passed through a hammer mill to produce particles essentially below 100 microns. All other compounds of this invention can be formulated in a like manner.

lwtruded Pellet Percent 3-eyelohesyl-h.7-dihydro-X-methylimida/o-l l. 2-n |-s-tria/ine-2.-lt .-H.NH l-dione anhydrous sodium sulfate ll); crude calcium ligninsulfonnte 5' sodium alkylnaphthylenesult'onate v 1'; calcium magnesium bentonite 9) limidazo-l 1.2-a Is-triaIineZA-t 3H.NH l-dione 4t); dioctylsodium sulfosuccmate 1.5; sodium ligninsulfonatc 3'] lo viscosity methyl cellulose L5) attnpulgite 5-1;

The ingredients are thoroughly blended. passed through an air mill to produce an average particle size under 15 :microns. reblended. and shifted througha U.S.S. No.'.5() sieve (0.3 millimeters opening) before packaging. All the compounds of the invention may be formulated in the same manner.

Aqueous Suspension lcrctnt 3-( 4-t-butylcyelohexyl )-b.7dihydro-Sanethyf limidazo-l 1.2m|-stt'i;tZittc-2.4-(3H.XH l-dione 25' hydrated attapulgite 3' crude calcium ligninsulfonate 10'; sodium dihydrogen phosphate 0.5; water i 61.5;

The ingredients are ground together in a ball or roller mill until the solid particles'have been reduced to diameters under it) microns.

High-Strength Compositions Percent 3-cycltthexyl-tn'ldihydro-K-methylimida/o-l l.- )0, 2-:1 |-s-tria'1.ine-2.4-l .HLNH )-dione synthetic silica 5': sodium lauryl sulfate 2" partially desulfonated sodium ligninsulfonate 3';

The above ingredients are ground to pass a 0.25 mm. screen. This product can be used directly or is suitable for further formulations.

Mixture lereent -eyclohesyl-o.7-dihydro-Kmethylimidazo-l l.-

s-triawine-'..-l-t3Hk1l-ll-dione 25 diuron 5U; altapulgite clay It); synthetic silica 2' sodium alltylnaphthylene sulfonalc 2; sodium ligninsulfonate 15 The above ingredients are blended and hammer milled to a particle size essentially below microns followed by reblcnding.

Use of the Compounds The compounds of formula 1 are useful for the control of undesired vegetation. They are broad spectrum herbicides ideally suited to destroy weeds on industrial sites. parking lots. railroad yards. around farm buildings. ctc. The compounds can be applied both preemergence. and postemergence.

The precise amount to be used in anygiven situation will vary according to the length ofcontroldesired. the use involved-the plant species and soil type. the mode of application. prevailing weather conditions. foilage density. and like factors. Hence. it is not possible to state a rate of application suitable for all situations: however. generally. the compounds of this invention are used at levels-of about one kilogram per hectare to about 25 kilograms per hectare.

'l'he herbicidal activity of the compoundspf this invention is demonstrated by the following greenhouse tests. Seeds of crabgrass (Digitarria spp.). barnyardgrass (Echinochloa crus-galli). wild oats (Avena Fatua). Cassia tora. morning glory (lpomoea spp.). cocklebur (Xanthium spp.). sorghum. corn. soybean. rice. wheat. and nutsedge tubers were planted in a growthmiedium and treated preemergence with the chemicals dissolved in a non-phytotoxic solvent. Atth e same timecotton having five leaves (including cotyle donary ones) bush beans with'the third trifoliate leafcxpanding. crabgrass with two leaves. barnyardgrass with two leaves. wild oats. with one leaf. cassia with I three leaves (including cotyledonary ones). morning glory with four leaves (including cotyledonary ones). cocklebur with four leaves (including'cotyledonary ones). sorghum with three leaves. corn with three leaves. soybeans with two cotyledonary leaves. rice' with two leaves. wheat with one leaf. and nutsedge'with:- 3-5 leaves were sprayed. Treated plants and controlswere maintained in a greenhouse for 16 days then all' species were compared to control and visually rated for response to treatment. A qualitative (type of plant response):rating was made. The letter C. indicates chloro-.,

sis/necrosis. A quantitative on a scale ol' to l() was also made. A rating of means no effect. A rating of means maximum effect. for example. complete kill in the case ofehlorosis. Results obtained in this test for one ofthe compounds ofthis invention are given in the following table.

i in

Morningglory (ucklcbur ('assia Nutsedgc ('rabgrass Barnyartlgrass Wild Oats What is claimejdis: 1 l. A compound of the formulaz wherein Q is hydrogen. fluorine. *chlorine. bromine. alkyl of I through 4 carbon atoms. alkoxy. or alkylthio of 1 through 2 carbon atoms. nitro. or triflu'oromethyl:

Y is hydrogen. chlorine. or methyl; and

Z is hydrogen or chlorine; the above alkyl. groups substituted with one methoxy. ethoxy. methylthio. or ethylthio group: the above cycloalkyl groups substituted with one alkyl of 2 through 4 carbon atoms. 1 through 2 methyl groups. I through 2 chlorines or bromines. one methoxy or one ethoxy group:

R is hydrogen or methylz and n is 2 or 3.

2. A compound of claim I wherein R 'is alkyl of 3 through 6 carbon atoms. cycloalkyl of 5 through 8 carbon atoms. or cyc'loalk'yl of 5 through 8 carbon atoms substituted with 1 methyl group; R. is methyl; and n is v 6.7-dihydro-8-methyl-imidazol l.Z-a]-s-triaZine-2.4- (3H.8H)-Llit)nc.

3'. The compound of claim 2 .which is 3 -cyclohcxyl 1 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3, 907, 796

DA ED I September 23, 1975 INVENT I Richard A, Jewell and Kang Lin It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

At column 11, approximately line #5; at columns l2, l3, l t, 15 and 16, at approximately line 5 of each; and at claim 1, line 2 (column 20, approximately line 15) the formula should be:

0 N N-Rz Signed and Scaled this twenty-fifth Day of May 1976 [SEAL] A lies I:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner oflarenrs and Trademarks 

1. A COMPOUND OF THE FORMULA:
 2. A compound of claim 1 wherein R1 is alkyl of 3 through 6 carbon atoms, cycloalkyl of 5 through 8 carbon atoms, or cycloalkyl of 5 through 8 carbon atoms substituted with 1 methyl group; R2 is methyl; and n is
 2. 3. The compound of claim 2 which is 3-cyclohexyl-6,7-dihydro-8-methyl-imidazo(1,2-a)-s-triazine-2,4-(3H,8H) -dione. 